The significance of the discovery of X-ray laws in the field of optics

Millikan, R. A. and Bowen, I. S.
(1925)
The significance of the discovery of X-ray laws in the field of optics.
Proceedings of the National Academy of Sciences of the United States of America, 11
(2).
pp. 119-122.
ISSN 0027-8424.
http://resolver.caltech.edu/CaltechAUTHORS:MILpnas25a

Abstract

The Extension of Moseley's Law to the Field of Optics. Through our recent stripping of all the valence electrons from one up through seven from the whole group of atoms, sodium, magnesium, aluminum, silicon, phosphorus, sulphur and chlorine, and from one up through five from the group, lithium, beryllium, boron, carbon and nitrogen, we have obtained for the first time a long series of light atoms having an identical electronic structure, but a linearly increasing nuclear charge. It is precisely this combination of identity of internal electronic structure among heavy atoms with linearly increasing nuclear charge which is responsible for the existence of the Moseley Law in the X-ray field, and the so-called irregular-doublet law, which flows from it.